One of the most widely accepted home networking technologies is UPnP. The UPnP standard enables devices such as personal computers (PCs), televisions, set-top boxes and mobile phones to automatically discover each other, connect, and interoperate seamlessly. UPnP is a fundamental building block of the DLNA specification, which may be currently considered a de facto standard for home network interoperability.
The deployment of SIP and Internet Protocol multimedia subsystem (IMS) has made IP-based video telephony a much more compelling business proposition for mobile carriers than in the past. This service provides the ultimate “friends-and-family” experience, enabling users to connect face-to-face, over any distance, as if they were in the same room.
As can be appreciated, video telephony services typically require dedicated videophones or mobile phones with built-in cameras. In other cases, webcams are used with computer soft clients. Most of these devices are built upon SIP technology that can establish, modify and terminate multimedia sessions or calls.
This video service becomes even more compelling if it can be enabled without requiring dedicated SIP video devices at both endpoints. For example, it could be desirable to provide the capability for a video stream initiating from a SIP-enabled mobile phone in a wide area network to be displayed on a non-SIP-enabled television in a home instead of on the small screen of another SIP-enabled mobile phone in that same home. However, this functionality would require the ability to redirect the SIP-based video stream to non-SIP devices, such as a television, on the local area home network.
As discussed above, SIP is used primarily as a protocol for communications (e.g., video streaming) over a wide area network, while UPnP and DLNA are used to communicate over a local network, such as home or local area networks. As can be appreciated by one skilled in the art, it is generally considered impractical to modify the base of UPnP and DLNA consumer electronics devices that have been installed in the home or local area network to accommodate SIP-based video streaming.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.